Marijuana and its derivatives have been shown to reduce intraocular pressure when administered systemically in human subjects. The mechanism of this action has not been fully elucidated. To date studies have been concerned with systemic administration and its ocular effects in subjects with normal intraocular pressure and not in individuals with ocular hypertension or glaucoma. No data is available on the feasibility of topical ocular administration in humans, or its effect on intraocular pressure. The objectives of the present study are: 1) to evaluate the feasibility of topical ocular usage of marijuana derivatives in human eyes; 2) to evaluate the effect of topical application of marijuana derivatives on intraocular pressure, outflow facility, scleral rigidity, episcleral venous pressure, pseudofacility, and aqueous flow in human eyes; 3) to evaluate these compounds in normal eyes, in eyes with ocular hypertension without visual field loss, and in eyes with open angle glaucoma with visual field loss; 4) to compare various derivatives of marijuana for an effect on intraocular pressure, as well as determining the most useful vehicle for these derivatives, and to establish dose- response curves for the effective compounds; 5) to determine how concurrent usage of other glaucoma medications affects or is affected by the compounds being tested.